Swift3将字符串值转换为十六进制字符串

Question

我是Swift的新手，我希望将字符串转换为十六进制字符串。我发现 Objective-C 函数将字符串转换为十六进制。

NSString * str = @"Say Hello to My Little Friend";

NSString * hexString = [NSString stringWithFormat:@"%@",
[NSData dataWithBytes:[str cStringUsingEncoding:NSUTF8StringEncoding]
                                         length:strlen([str cStringUsingEncoding:NSUTF8StringEncoding])]];

for (NSString * toRemove in [NSArray arrayWithObjects:@"<", @">", @" ", nil])
    hexString = [hexString stringByReplacingOccurrencesOfString:toRemove withString:@""];

NSLog(@"hexStr:%@", hexString);

现在我无法在Swift中转换此函数。目前我正在使用Swift3。

请有人可以帮我吗？

Answer 1

这产生与ObjC版本相同的输出

let str = "Say Hello to My Little Friend"
let data = Data(str.utf8)
let hexString = data.map{ String(format:"%02x", $0) }.joined()

Answer 2

将您的字符串转换为NSData，如下所示。

let myString = "ABCDEF"
let data = myString.dataUsingEncoding(NSUTF8StringEncoding)

然后使用以下方法将NSData转换为十六进制字符串 -

func hexFromData(data:NSData) -> String {
    let p = UnsafePointer<UInt8>(data.bytes)
    let len = data.length
    var str: String = String()
    for i in 0...len-1 {
        str += String(format: "%02.2X", p[i])
    }
    return str
}

希望这会有所帮助。

Answer 3

请试试这个，

let string = "Say Hello to My Little Friend"
let data = string.dataUsingEncoding(NSUTF8StringEncoding)
print(data)

，其输出为：

  Optional(<53617920 48656c6c 6f20746f 204d7920 4c697474 6c652046 7269656e 64>)

Answer 4

详细信息

• Xcode 11.2.1（11B500），Swift 5.1

解决方案

@GET("/friends")
 Call<ResponseBody> friends(@Query(value="group", encoded=true) String group);

用法

extension String {
    func toHexEncodedString(uppercase: Bool = true, prefix: String = "", separator: String = "") -> String {
        return unicodeScalars.map { prefix + .init($0.value, radix: 16, uppercase: uppercase) } .joined(separator: separator)
    }
}

Answer 5

  

Swift 3

let string = "Hello World!"
let data = string.data(using: String.Encoding.utf8)

let hexString = data?.hex


extension Data {

var hex: String {
        var string = ""

        #if swift(>=3.1)
            enumerateBytes { pointer, index, _ in
                for i in index..<pointer.count {
                    string += String(format: "%02x", pointer[i])
                }
            }
        #else
            enumerateBytes { pointer, count, _ in
                for i in 0..<count {
                    string += String(format: "%02x", pointer[i])
                }
            }
        #endif

        return string
    }


}